The present invention relates to a novel and useful system for testing the electrical integrity of an illuminated exit sign.
Illuminated exit signs are required by law to be placed in edifices to indicate egress from a structure as a matter of convenience and during periods of emergency. It is, thus, important that such exit signs be reliable, being provided with a constant supply of electrical power to maintain illumination of the exit signs at all times. Along these lines, it is imperative that the integrity of the electrical system of an illuminated exit sign be tested at selected intervals to ensure that power is always available to the exit sign under all conditions. That is to say, the existence of a battery, the integrity of the battery, the charging system for the battery, and the like, must constantly be determined.
In the past, many testing procedures for illuminated exit signs have been accomplished manually by roving personnel. Written records must also be kept of such visual inspections and tests for review by legal entities having jurisdiction over such matters. Recently, many rules and regulations have permitted the use of self-testing and self-diagnostic illuminated exit signs operated by a battery, in conjunction with limited visual inspections by personnel. Thus, it is advantageous to provide illuminated exit signs that are capable of accomplishing such self-tests.
U.S. Pat. Nos. 3,384,886, 4,088,986, and 4,544,910 describe emergency lighting and exit sign systems that include indicators showing the existence of stand-by power, the proper level of voltage of the stand by power and the integrity of a battery.
U.S. Pat. No. 4,199,754 shows a circuit for an emergency lighting and fire detection system which latches an emergency light in an off position indicating that a low voltage condition exists in the battery power source.
An exit sign which is capable of continually self testing and retesting source of battery power and recharging system for such battery would be a notable advance in the emergency lighting field.